旱地玉米免耕覆盖土壤水分研究  

Study on Soil Water under No-tillage with Stalks Mulching in Semi-arid region

作　　者：籍增顺[1] 王盛霞 洛希图[1] 张象俊 武金芳 

机构地区：[1]山西省农业科学院农业资源综合考察研究所,汾阳县区划办

出　　处：《山西农业科学》1994年第3期7-12,共6页Journal of Shanxi Agricultural Sciences

摘　　要：免耕整秸秆半覆盖具有明显的保水效果。在一年一作春播玉米区，免耕覆盖抑制了土壤水分蒸发，延长了上层水分向深层分布的时间，玉米秋收后至结冻期间１００～２００ｃｍ土壤水分比不覆盖提高１～１．６个百分点；但结冻期间，土壤水分蒸发基本停止，０～１００ｃｍ土层水分差异不大；免耕覆盖明显抑制了春季返浆期的土壤蒸发，０～２０ｃｍ土层比常规耕作土壤水分含量高１～１．７个百分点；玉米生育期间，土壤水分变化规律是，封垄前覆盖与不覆盖间土壤水分差异较大，封垄后差异变小；一般情况下，随深度增加，保水效果减小。免耕本身不具保水作用；在覆盖条件下，耕翻与否对保水作用不大，不论是耕翻还是免耕都必须结合秸秆覆盖；随秸秆覆盖量的增加，土壤第一蒸发阶段持续时间增长，土壤蓄保水量增加；秸秆覆盖一方面具有保水效果，另一方面，降水通过秸秆时又要消耗一定量的水分；免耕覆盖改变了地表状况，有利于雨水的入渗，使得更多的水分下移到剖面深层，为植物利用水分提供了机会；持续干旱情况下，秸秆覆盖土壤水分蒸发量与裸露土壤几乎一样多。Experimental results at six locations from 1990 through 1992 indicated that, in the regions of growing one crop a year, soil water content at 100～200cm depth during period from October to November increased 1～1. 6 percent point under no-tillage with mulching than conventional tillage. Soil water content of freeze period at 0～100cm depth were nearly the same, but increased 1～1. 7 percent point before spring sowing at 0～20cm depth. As season and depth prograssed, soil water differences between no-tillage with mulching and conventional tillage became small. Under no-tillage without mulching, soil water content was the same with conventional tillage. When a mulch of protective material was used on the surface of the soil, infiltration of water into a mulched soil was maintained at a higher rate for a longer period of time. If the rains were infrequent, the cumulative moisture loss on a mulched soil would lag behind a bare soil but eventually will reach approximately the same moisture content in the total profile.

关 键 词：免耕 覆盖 土壤水分 玉米 旱地 

分 类 号：S513.051[农业科学—作物学]